1. Field of the Invention
The present invention relates generally to safety devices for the protection of occupants of moving vehicles. More particularly, the present invention relates to a seatbelt assembly having an integral airbag, and which is mountable in an automobile or the like.
2. Background Art
In recent years, the value of airbags which inflate in response to collisions to protect the occupants of automobiles and other moving vehicles has become widely recognized. Such airbags have proven highly effective in reducing the rate of injury to occupants of vehicles which are so equipped, particularly when such airbags are used in conjunction with conventional seatbelts, such as lap and shoulder belts.
Despite the fact that the benefits of such airbags are now well known, relatively few vehicles are provided with this equipment; for example, airbags have been installed in automobiles only during the most recent model years, and even then have been installed only in certain models. Furthermore, even in those models which are equipped with airbags, airbag protection is typically provided only for the driver; airbag installations for protection of front seat passengers are relatively rare, and are virtually nonexistent for rear seat passengers. Nevertheless, both of these groups of passengers are in need of protection by airbag installations; for example, the rear seat occupants of vehicles having only rear lap belts suffer a high incidence of spinal injuries which might be prevented by the use of airbags.
In a conventional automobile, the airbag protection for the driver is most typically installed in the hub of the steering wheel. The airbag itself is a folded, expansible, bag constructed of a suitable fabric. A solid rocket fuel charge is connected to communicate with the interior of the airbag. Upon impact, a firing circuit ignites the rocket fuel charge, which in turn very rapidly generates a gas discharge which fills the bag. The bag escapes from the steering wheel hub and expands in front of the driver, thereby cushioning the driver as he is thrown forward by frontal impact and preventing him from coming into contact with the hard interior surfaces of the vehicle. The airbag then quickly deflates so as to permit the driver to regain control of the vehicle (if it is still moving) and to facilitate egress from the vehicle. This arrangement, while it has proven highly effective in providing protection for the driver, does not lend itself to being retrofitted to vehicles which lack an original equipment airbag protection system. Similarly, the few existing passenger side airbag systems involve airbags mounted in or under the dashboard of the vehicle, which is once again an arrangement which is difficult to retrofit to older vehicles. Furthermore, it will be appreciated that in both of these conventional arrangements the airbag is necessarily positioned in front of the driver/passenger, which provides protection in the event of a frontal impact, but which provides limited, if any, protection in the event of a side impact.
Still further, although the airbag systems described above have proven highly effective in cushioning the impact of the passenger during an accident, there still exists the danger that materials may pierce the airbaq and impact the passenger's body. For examine, the steering column of the vehicle may be driven rearward through the airbag and into the body of the driver.
Accordingly, there exists a need for a system which can provide airbag protection for each of the occupants of the vehicle, including both the front and rear seat passengers as well as the driver. Furthermore, there is needed such a system which can be inexpensively retrofitted to older vehicles not having airbags installed as original equipment. Moreover, there is a need for such an airbag system which reduces the risk of components of the motor vehicle penetrating the bag and coming into contact with the body of the passenger.